Ukrainian Pravda said on 5 May that Boris Johnson persuaded Zelensky not to continue negotiations with Putin

The Ukrainska Pravda article is here. I quote from it in translation, via Zero Hedge.

Possibility of talks between Zelenskyy and Putin came to a halt after Johnson’s visit - UP sources

IRYNA BALACHUK, ROMAN ROMANIUK —  THURSDAY, 5 MAY 2022, 13:32

Following the arrival of British Prime Minister Boris Johnson in Kyiv, a possible meeting between Ukrainian President Vladimir Zelenskyy and Russian President Vladimir Putin has become less likely.

The Russian side…was actually ready for the Zelenskyy-Putin meeting.

But two things happened, after which a member of the Ukrainian delegation, Mykhailo Podoliak, had to openly admit that it was "not the time" for the meeting of the presidents. 

The first thing was the revelation of the atrocities, rapes, murders, massacres, looting, indiscriminate bombings and hundreds and thousands of other war crimes committed by Russian troops in the temporarily occupied Ukrainian territories…

The second "obstacle" to agreements with the Russians arrived in Kyiv on 9 April."

According Ukrainska Pravda sources close to Zelenskyy, the Prime Minister of the United Kingdom Boris Johnson, who appeared in the capital almost without warning, brought two simple messages.

The first is that Putin is a war criminal, he should be pressured, not negotiated with.

And the second is that even if Ukraine is ready to sign some agreements on guarantees with Putin, they are not.

Johnson’s position was that the collective West, which back in February had suggested Zelenskyy should surrender and flee, now felt that Putin was not really as powerful as they had previously imagined, and that here was a chance to "press him."

Three days after Johnson left for Britain, Putin went public and said talks with Ukraine "had turned into a dead end".

Three days later, Roman Abramovich arrived in Kyiv again, and President Zelenskyy officially stated that there could be two security agreements with Russia: one would concern Ukraine's coexistence with Russia, the other - only security guarantees, because not everyone "sees themselves at the same table with the Russian Federation ".

After that, according to Ukrainska Pravda sources, the bilateral negotiation process was paused.